Polymeric fluorescent substrate and polymer light-emitting device using the same
A polymeric fluorescent substance exhibiting visible fluorescence in the solid state, having polystyrene reduced number average molecular weight of 1×10 3 to 1×10 8 , and comprising one or more repeating units of following formula (1), wherein Ar 1 and Ar 2 each independently represent an arylene group or the like; Ar 3 represents an aryl group or the like having one or more substituents of formula (2) as nuclear substitution; X represents —CR 1 ═CR 2 — or —C≡C—; and n is 0 or 1, —Y—Ar 4 (2) wherein Ar 4 represents an aryl group or the like; and Y represents —CR 3 ═CR 4 — or —C≡C—. The triarylamine type polymeric fluorescent substance is excellent in quantum yield of fluorescence and in light emitting efficiency when made into a device.
1. A polymeric fluorescent substance exhibiting visible fluorescence in the solid state, having polystyrene reduced number average molecular weight of 1×10 3 to 1×10 8 , and comprising repeating units of following formula (1) in the main chain,
wherein Ar 1 and Ar 2 each independently represent an arylene group or a divalent heterocyclic compound group; side chain Ar 3 represents an aryl group having one or more substituents of formula (2) or represents a heterocyclic group having one or more substituents of formula (2) as nuclear substitution; X represents —CR 1 ═CR 2 — or —C≡C—; R 1 and R 2 each independently represent a group selected from a hydrogen atom, an alkyl group, an aryl group, a monovalent heterocyclic compound group, and cyano group; n is 0,
—Y—Ar 4 (2)
wherein Ar 4 represents an aryl group, a monovalent heterocyclic compound group or a monovalent aromatic amine group; Y represents —CR 3 ═CR 4 — or —C≡C—; R 3 and R 4 each independently represent a group selected from a hydrogen atom, an alkyl group, an aryl group, a monovalent heterocyclic compound group and cyano group.
2. A polymeric fluorescent substance according to claim 1 wherein the total amount of repeating unit represented by formula (1) is 1% by mole or more and 100% by mole or less based on all repeating units.
3. A polymeric fluorescent substance according to claim 1 or 2 comprising one or more repeating units of formula (1) and one or more repeating units of the following formula (3),
—Ar 5 —(Z)p— (3)
wherein Ar 5 represents an arylene group or a divalent heterocyclic compound group; Z represents —CR 5 ═CR 6 — or —C≡C—; R 5 and R 6 each independently represent a group selected from a hydrogen atom, an alkyl group, an aryl group, a monovalent heterocyclic compound group, and cyano group; and p is 0 or 1.
4. A polymeric fluorescent substance according to claim 3 wherein the total amount of repeating units represented by formula (1) and formula (3) is 50% by mole or more based on all repeating units; the repeating unit represented by formula (1) is 2% by mole or more and 90% by mole or less, and the repeating unit represented by formula (3) is 10% by mole or more and 98% by mole or less, based on the total amount of repeating units represented by formula (1) and formula (3).
5. A polymer light-emitting device comprising at least a light emitting layer between a pair of electrodes composed of anode and a cathode at least one of which is transparent or semi-transparent wherein the light emitting layer comprises a polymeric fluorescent substance according to any one of claims 1 to 4 .
6. A polymer light-emitting device according to claim 5 wherein a layer containing a conductive polymer is disposed between at least one of the electrode and a light emitting layer such that the layer containing a conductive polymer is adjacent to said electrode.
7. A polymer light-emitting device according to claim 5 wherein an insulating layer having a film thickness of 2 nm or less is disposed between at least one of the electrode and a light emitting layer such that the insulating layer is adjacent to said electrode.
8. A flat light source comprising a polymer light-emitting device according to claim 5 .
9. A segment display apparatus comprising a polymer light-emitting device according to claim 5 .
10. A dot-matrix display apparatus comprising a polymer light-emitting device according to claim 5 .
11. A liquid crystal display comprising a polymer light-emitting device according to claim 5 as a back light.
12. A flat light source comprising a polymer light-emitting device according to claim 6 .
13. A segment display apparatus comprising a polymer light-emitting device according to claim 6 .
14. A dot-matrix display apparatus comprising a polymer light-emitting device according to claim 6 .
15. A liquid crystal display comprising a polymer light-emitting device according to claim 6 as a back light.
16. A flat light source comprising a polymer light-emitting device according to claim 7 .
17. A segment display apparatus comprising a polymer light-emitting device according to claim 7 .
18. A dot-matrix display apparatus comprising a polymer light-emitting device according to claim 7 .
19. A liquid crystal display comprising a polymer light-emitting device according to claim 7 as a back light.